1. Field of the Invention
The invention relates to a method for material testing of an elongated work piece drawn through a drawing die arrangement, to the use of a drawing die arrangement, and to a drawing die arrangement.
2. Description of the Related Art
Such a drawing die arrangement is known from DE 10 2009 039 873 A1, whereby here, a drawing tool referred to as a drawing ring serves for shaping of the elongated work piece to be formed in the drawing method, in each instance. In particular, it is known from DE 10 2009 039 873 A1 to provide a material guide disposed ahead of the drawing ring, in each instance, in the drawing direction, by way of which the work piece to be drawn, in each instance, is fed to the drawing ring.
In the production of seamless pipes, using the drawing method, the work pieces to be drawn are configured in the form of hollow bodies. In this connection, a great technical challenge is presented in processing the work pieces during the drawing method so that the finished pipe or the finished drawn product has the most uniform possible mass distribution over the cross-section, or that the finished drawn product has a thickness expanse that remains as uniform as possible over the cross-section. For this purpose, it is proposed in DE 10 2009 039 873 A1 to configure a work piece guide disposed ahead of the drawing ring in the drawing direction—by way of which guide the work piece, in each instance, is fed to the drawing ring—so as to be displaceable relative to the drawing direction.
By suitable displacement of the work piece guide, and therefore ultimately also of the feed direction in which the work piece, in each instance, is fed to the drawing ring, the most uniform possible mass distribution can be made available in the drawn product to be produced by the drawing method, in that, for example, irregularities or uneven wall thicknesses or eccentricities of the work piece to be formed or shaped, in each instance, which can have an influence on the quality of the formed work piece, are evened out by suitable displacement of the work piece guide. In this connection, it is known from DE 10 2009 039 873 A1 to determine the displacement of the work piece guide, in each instance, that is required for the production of a drawn product having the most uniform possible mass distribution in cross-section, in that the mass distribution of the work piece material is measured in cross-section, and the work piece guide is displaced in accordance with the measured mass distribution. A corresponding measurement of the mass distribution is also disclosed by DE 29 12 996 C2.
Corresponding drawing die arrangements and drawing systems having drawing machines that draw the work pieces through the drawing die arrangement are also known for drawing rods, in other words for drawing elongated work pieces composed of a solid material. It makes little sense to measure a mass distribution here. Such a parameter is irrelevant for quality because solid material is involved.
Not only drawing of rods but also drawing of pipes, in other words drawing of all work pieces, generally involves processes that take place at the end of a production process, with regard to the semi-finished products produced, in each instance, in other words, for example, after casting and after rolling, and accordingly are considered part of final production. Here, in particular, material properties of the work pieces being processed are of significant importance, whereby suitable material testing methods or apparatuses, which allow statements about defects in the drawn, elongated work pieces, for example, cannot be found, specifically those that are suitable for the sector of drawn work pieces.